Cache regex permissions when they get processed

common/src/main/java/me/lucko/luckperms/common/calculators/processors/RegexProcessor.java

@@ -57,7 +57,10 @@ public class RegexProcessor implements PermissionProcessor {
                 continue;
             }
 
-            regexPermissions.put(e.getKey().substring(2), e.getValue());
+            String pattern = e.getKey().substring(2);
+            Patterns.compile(pattern); // Cache the lookup for later.
+
+            regexPermissions.put(pattern, e.getValue());
         }
     }
 }

common/src/main/java/me/lucko/luckperms/common/constants/Patterns.java

@@ -61,6 +61,7 @@ public class Patterns {
         try {
             return CACHE.get(regex);
         } catch (UncheckedExecutionException | ExecutionException e) {
+            e.printStackTrace();
             return null;
         }
     }